Effects of detector threshold, location of the sun, and flight altitude upon spectral variations in remote sensing over waterPhotographic flights with Hasselblad cameras were flown on August 28, 1975, at altitudes from 2.66 and 5.3 kilometers over an ocean acid waste dump site while acid dumping was in progress. Repeated flights resulted in broadband spectral radiance data between the wavelengths of 500 to 900 nanometers for sun elevation angles that varied from 26 to 48 degrees, and at all sun azimuth angles over the range of off-nadir angles from 0 to 35 degrees. From film densitometer data, it is shown that before spectral variations in remotely sensed data can be used to quantify substances in water, the longer wavelength data must be above the detection level of the detector, radiance data between + or - 45 degrees in the direction of the sun must be avoided, and off-nadir camera correction factors must be applied to the observed radiance data.
Document ID
19780050948
Acquisition Source
Legacy CDMS
Document Type
Conference Proceedings
Authors
Bressette, W. E. (NASA Langley Research Center Marine and Applications Technology Div., Hampton, Va., United States)
Date Acquired
August 9, 2013
Publication Date
January 1, 1977
Subject Category
Environment Pollution
Meeting Information
Meeting: Annual Remote Sensing of Earth Resources Conference